1. Field of the Present Disclosure
The present disclosure relates to an image forming apparatus.
2. Description of the Related Art
In order to restrain toner density fluctuation due to eccentricity of a photoconductor drum and/or a development roller, an image forming apparatus detects a value of an alternating current induced by a development bias, and adjusts a direct current component of the development bias on the basis of the detected value of the alternating current and thereby performs toner density adjustment.
Specifically, the eccentricity results in changing a distance between the photoconductor drum and the development roller, and consequently a capacitance between them also changes. The value of the alternating current induced by the development bias is changed in accordance with the change of the capacitance between them, and therefore, on the basis of the value of the alternating current, the toner density is adjusted so as to restrain toner density fluctuation due to eccentricity of a photoconductor drum and/or a development roller.
However, in the aforementioned image forming apparatus, the toner density adjustment is performed uniformly in a primary scanning direction (i.e. an axis direction of the photoconductor drum and the development roller), and therefore, if the toner density fluctuation occurs along the primary scanning direction, the toner density fluctuation along the primary scanning direction is not adequately restrained.
For example, if an axis of the photoconductor drum and an axis of the development roller are not in parallel to each other and one of them tilts to the other, then a toner density at one end of a printable range in the primary scanning direction is higher than a toner density at the other end of the printable range. However, such toner density fluctuation is not restrained in the aforementioned image forming apparatus. Similarly, if an axis of the photoconductor drum or an axis of the development roller is curved or bent, then a toner density at a center portion a printable range in the primary scanning direction is higher than a toner density at both ends of the printable range. However, such toner density fluctuation is not restrained in the aforementioned image forming apparatus.